1. Field of the Invention:
This invention relates to an invasive probe system for use in both industrial and medical applications and, more particularly, to invasive probe systems of the type having a probe head interconnected to a controller by a signal-carrying position control cable having means for articulating the probe head.
2. Description of the Prior Art:
Invasive probe systems of the general type set forth above are known, such as are disclosed e.g. in U.S. Pat. No. 4,748,969 (Wardle), U.S. Pat. No. 4,530,568 (Haduch et al.), U.S. Pat. No. 4,834,102 (Schwarzchild et al.), and U.S. Pat. No. 4,633,882 (Matsuo et al.). The probe heads utilized in such systems uniformly include electronic, optical or acoustical (ultrasonic) imaging devices and thus require a remote position control cable having a signal-carrying capability, with a multichannel capacity being highly preferred for increased resolution. The probe heads also may be configured for effecting treatment of some sort upon correct positioning. The need to image mechanical parts or body organs hidden from view along a probe entry path, or at least in a position oblique to the path, requires the system to be capable of articulating the probe head to some degree relative to the longitudinal probe insertion path.
Conventional systems have attempted to solve the problem of articulation in a variety of ways, including the use of vertebrae-like devices connecting the cable to the probe head and the use of cable structures capable of controlled bending along the cable centerline. These conventional solutions use control wires or sheaths disposed along the control cable usually in conjunction with a frame-like member in the cable to actuate the vertebrae devices while preventing cable deformation, or to provide controlled bending of the cable itself. In either case, the cable frame members can add unacceptably to the cable diameter or restrict the cross-sectional area available for signal-carrying or treatment conduits.
Conventional vertebrae connecting devices generally utilize vertebrae units restricted to two-dimensional motion between any two adjacent units and depend upon connecting pairs being angularly offset, relative to the vertebrae longitudinal axis, to achieve a three-dimensional articulation capability which is highly desirable. Moreover, the pin-type hinge attachment between vertebrae units in conventional devices can also restrict the angular deflection between adjacent units, thereby possibly unduly increasing the number of units required to achieve a desired probe head angular deflection.
Finally, the controllers used in conventional systems typically use hand-driven rotary knobs extending from the controller housing to actuate the control wires to provide the relative longitudinal movement giving rise to the forces which cause the bending in the vertebrae device or the control cable itself. The controllers generally are themselves hand-held, and the knobs can require the use of the other hand for operation thereby restricting the operator's ability to simultaneously adjust other instrumentation, such as the scanning control devices. Also, the conventional controllers use ratchet-type mechanical stops for fixing the probe head position. These can further complicate the operation of the controller and be ineffective to provide fine control of probe head position.